F(b)=7b+8
you just need to change the x variable. make y into f(x) or in this case f(b)

notice, it goes 4,6 then 4, 6 again, and so on and so on
based on whatever exponent it may have
now, you're being asked, what 214 will give? 4 or 6?
Answer: 11.4 m
Step-by-step explanation:
The scenario depicted is that of a right angled triangle with the 7 meters being the base and the 9 meters being the height.
The length of the ladder will therefore be the Hypothenuse.
Using the Pythagorean Rule:
a² + b² = c²
with c being the hypothenuse
7² + 9² = c²
49 + 81 = c²
c²= 130
c = √130
c = 11.4 m
33+33+3^0 = 100
(in case you didnt know the third one is three to the power of 0)